Chromium (VI) reagents have been widely used in organic chemistry for the oxidation of primary and secondary alcohols to carbonyl compounds. Pyridine-chromium trioxide complexes and pyridinium chlorochromate have been especially useful reagents for the mild oxidation of primary alcohols to aldehydes. There are, however, some significant difficulties associated with the reagents. For instance, chromium containing by-products often contaminate the desired products, requiring time consuming purifications. Also, polymeric, chromium containing tars are formed which contaminate both the reaction and work-up apparatus.